Pocket-size circuit tester



NOV. 20, 1951 w, c, LINTQN 2,575,821

POCKET-SIZE CIRCUIT TESTER Filed Oct. 21, 1948 I 1 r IIII.VIIIII r11 11/11/111/I!r//llIll//l// Inn-" "null";

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wiffiq wv Q- WOW ATTO R N E76 Patented Nov. 20. 1951 UNITED STATES PATENT OFFICE POCKET-SIZE cmeun: TESTER William 0.. Linton, Washingtomll). c.

ApplicationOctober 21, maserml M55314 The present invention relates to "lamp type line, circuit or fuse testers-and an object of the "invention is to proVideapocket-size tester of the above T character of a new :and novel construction *inwhich the several parts thereof :may be easily and readily constructed and assembled together for reducing the cost associated with the manufacture thereof to render the same commercially desirable.

Another object -'of the invention is to provide a tester "of this character with a supporting casing in which the lamp thereof -maybe housed in a casing moulded in one unitary structure sufficiently opaque as to hide from view the lamp and connections housed therein and having sections thereof --sufiiciently translucent as-to permit light rays from the lamp to pass therethrough and emit therefrom.

Gther objects -of the inventionwill be in part obvious and in part epointed out 'ahereinafter as the description thereof continues.

.-In the accom anying drawings:

Fig. l is a side elevation of the tester embodying the present invention.

Fig. 2 is another side elevation taken at right angles to Fig. 1.

Fig. 3 is a vertical cross sectional view.

Fig. 4 is an enlarged longitudinal section through the lamp housing.

Fig. 5 is a transverse section taken on the line 5-5 of Fig. 4 in the direction of the arrow points.

Fig. 6 is a plan view partly in section of the retaining plug, and

Fig. '7 illustrates in section a cover for the tester.

The line tester as herein shown comprises a combined holder and lamp housing I moulded in the form tube with one end 2 thereof closed. Arranged within this tube is a miniature neon glow lamp 3 having one lead wire thereof connected to the resistor 4 and the other lead wire of the lamp connected to a covered wire conductor 5. The resistor 4 being connected to the other covered wire conductor 6. The o posite ends of the conductors 5 and B are provided with the usual con tact points I and insulated coverings 8 extend over the connections between the contact points and their conductors wires. A se arator 9 consisting of a sheet of fibre is placed between the bare wires leading from the lamp to the conductor wires and its opposite ends are positioned between the base of the lam and a retaining lug In for supporting the lamp within the closed end 2 of the casing I. The retaining plug III has formed therethrough a pair of open- 2 ings I I each with oneside extending through the --outer peripheria1 wall of the plug throughwhich extend the conductor wires 5 and 6. The outside diameter of thecovering for these wires-5 and-6 is "slightlylarger than the diameter of openings H whereby when the plug 1!] is forced within the openedend 12 of the casing I a binding fit is-ef- *fected'between the covering for the conductors 5-and6 and the casing which securely holds the :plug within the casing aswouldprevent'the lamp and resistor housed therein from being withdrawn by pulls upon the conductor wires 5 andfi 'intheir normal use.

-A'clip I3 is securedbymeans of a rivet to the casing l as shown whereupon the tester maybe secured to a person's pocket carrying the same. 'Attimes the clip vl3 may be removed and the conductor wires 5 and '6 together with their con- .tact points may be folded and inserted within a cover ill. The opened end of this cover friction- .ally engages over the openedend of the casing I and bymeans of "the clip l3 secures to the cover the entire assembly may be retained and carried in ones pocket.

The casing or lamp housing I is preferably moulded from translucent urea moulding powders with a wall thickness that renders the lamp, resistor and other connections housed therein invisible from the outside thereof. However, certain sections l6 of the casing are moulded with a wall thickness of less than of an inch providing the reinforcing ribs l1 therebetween. The electrodes of the lamp are positioned adjacent the sections 16 of walls of the casing. These thin wall sections are sufficiently translucent as to permit the light rays from the lamp to pass therethrough and emit therefrom and still the lamp is not readily visible therethrough.

I claim:

1. A line tester of the character described comprising a casing moulded from translucent urea. moulding powders, a glow lamp housed within said casing, the wall of said casing having a thickness capable of being sufliciently opaque as to render the glow lamp housed therein invisible exteriorlv of the casing, the wall of said casing having depressions therein each forming a wall being of less thickness than that of the remaining wall thickness of the casing to provide window sections therein as will permit light rays from said lamp to pass therethrough and emit therefrom, reinforcing ribs formed with said casing and said reinforcing ribs separating said window sections of the casing from one another.

2. A line tester of the character described comprising in combination a translucent tubular casing, a, retaining plug for closing one end of said casing, the exterior diameter of said plug being substantially the same as that of the interior diameter of said casing, said plug having a pair of openings formed therein and extending therethrough, said openings each having a side portion thereof extending through the outer peripherial wall of said plug, a lamp housed within said translucent casing whereby light rays may pass therethrough and emit therefrom, a pair of covered conductor wires connected in series with said lamp and each having a portion thereof extending through the openings of said plug and the exterior diameter of said conductor wires being greater than that of the interior diameter of the openings within said plugwhereby when said plug is inserted within said casing a portion of the covering for said conductor wires will be forced through the portions of the openings extending through the peripherial wall of said plug to effect a binding fit between said casing and plug for retaining the latter therein.

3. A line tester of the character described comprising an elongated tubular casing having one end thereof closed, light emitting windows provided in said casing adjacent the closed end thereof, a lamp and resistor housed within said casing, a pair of conductors connected in series with said lamp and resistor and leading from said casing, a retaining plug for closing the open end of said casing, a portion of said conductors extending between said casing and plug for effecting a wedged fit therebetween, a fiber plate arranged between said conductors and said fiber plate being positioned between said retaining plug and the base of said lamp for retaining the latter adjacent the light emitting windows within the closed end of said casing.

4. A line tester of the character described comprising a cylindrical casing molded in one unitary piece of plastic material and having one end thereof closed, a lamp insertable through the open end of said casing and housed therein, the walls of said casing being of a thickness as to prevent the lamp housed therein from being viewed exteriorly of said casing, a window formed with said casing and being arranged adjacent the lamp housed therein, said window having a wall thickness less than that of said casing to render the same sufficiently translucent as to permit light rays from said lamp to pass therethrough and emit therefrom, but sufficiently opaque as to prevent the lamp housed within the casing from v being viewed exteriorly thereof, a plug for closing the open end of said casing and conductors leading through said plug to the lamp housed within the casing.

5. A lamp housing molded from urea molding powders in one unitary casing, the entire wall of said casing being of suificient thickness so as to render the same opaque as would prevent the lamp housed therein from being visible exteriorly thereof, said wall of the casing having portions thereof of less thickness than the remaining portions thereof as would render the same sufliciently translucent as would permit light rays from the lamp housed within the casing to pass therethrough and emit therefrom.

WILLIAM C. LINTON.

REFERENCES CITED Great Britain Oct. 29, .1931 

